This invention relates to a coalester filter and method for the removal of liquid from air and other gases.
A filter and method is illustrated in U.S. Pat. No. 4,801,313 and in continuation application Ser. No. 07/265,895 filed Nov. 2, 1988, now abandoned wherein a gaseous stream is directed from an orifice of lesser diameter upwardly directly into a column packed with coalescing material. Other patents of interest include U.S. Pat. No. 1,458,005, which discloses a vertical expansion chamber containing no coalescing material but through which an upward flow is created and passes through a foraminous partition into an absorbent material. Of further interest is U.S. Pat. No. Re. 32,989, wherein a downward gaseous flow is first initiated in a vertical column containing a coalescing material from whence the gaseous flow is carried laterally and upwardly into a column containing absorbent material. U.S. Pat. No. 4,822,387 illustrates the use of a cartridge containing coalescing material through which an upward air flow is carried although there is no air stream since the air flow occurs upwardly through the entire cross section of the cartridge. A float valve is positioned in a lower end of an envelope containing the cartridge at an upper end.
An air or gaseous stream as contemplated herein occupies at least initially a cross section less than the cross section of the column containing coalescing material. The stream is centrally disposed in that a substantial portion is intermediate or away from the inner wall of the column, as originating from the inlet orifice illustrated herein, to permit coalescence of liquid with downward flow thereof by gravity opposite the direction of the stream.
Accordingly, it is an important object of the present invention to facilitate the collection and discharge of coalesced liquid from the coalescing column of the filter.
Another object of the invention is the positive expulsion of the coalesced liquid from the collection canister to avoid the necessity of providing air flow to cause drainage as heretofore.
Another important object of the invention is to provide a collection canister for the coalesced liquid with an effective and efficient means of discharge as well as ease of servicing and effective mounting and sealing.
Another important object of the invention is to prevent large and expensive air loss, on a continuous basis, in the discharge of coalesced and collected liquids.
Another object of the invention is to prevent large pressure drops across the unit normally associated with the discharge of coalesced liquids.